threatening a global supply chain shock and slower economic growth. On the first of likely two days of talks, officials from the two superpowers were meeting at the ornate Lancaster House to try to get back on track with a preliminary agreement struck last month in Geneva that had briefly lowered the temperature between Washington and Beijing.

Since then the U.S. has accused China of slow-walking on its commitments, particularly around rare earths shipments. White House economic adviser Kevin Hassett said on Monday that the U.S. team wanted a handshake from China on rare earths after Donald Trump said Xi Jinping had agreed to resume shipments in a rare call between the two presidents last week. "The purpose of the meeting today is to make sure that they're serious, but to literally get handshakes," Hassett, director of the National Economic Council, told CNBC in an interview. He said the U.S. would expect export controls to be eased and rare earths released in volume immediately afterwards. (Reuters)